1. Field of the Invention
The present invention relates to an in-vivo information acquiring system provided with an in-vivo information acquiring apparatus introduced into an object to be examined and an external signal generating apparatus disposed outside the in-vivo information acquiring apparatus that operates the in-vivo information acquiring apparatus, and a method for controlling the in-vivo information acquiring system.
2. Description of the Related Art
In recent years, swallow type capsule endoscopes are making their debuts in the field of endoscopes. A capsule endoscope is introduced into a body by being swallowed from an examinee's mouth and moves inside a body cavity, for example, organs such as stomach and small intestine according to peristaltic movement and picks up images one by one until the capsule endoscope is spontaneously discharged.
Image data picked up in the body by the capsule endoscope while the capsule endoscope moves through the body cavity are transmitted one by one to the outside through wireless communication and stored in a memory provided in an outside receiver. By carrying the receiver, a patient can freely act after swallowing the capsule endoscope until the capsule endoscope is discharged.
The capsule endoscope obtains drive power from a battery or the like, which is built in a casing, but since the capsule endoscope has a structure with an inner circuit or the like hermetically sealed in the casing, a user cannot perform ON/OFF operation to drive the endoscope by operating a switch or the like disposed on the outer surface of the casing. Thus, an in-vivo observation system is proposed which is provided with a reed switch short-circuited/released by an outside magnetic field in the casing of a capsule endoscope.
For example, in a capsule endoscope 110 of an in-vivo observation system 101 disclosed by the present applicant in Japanese Patent Application Laid-Open Publication No. 2005-237460 shown in FIG. 1, power is distributed to a plurality of circuits by a DC magnetic field generated by coils 144 and 145 driven by current drivers 146 and 147 of an outside magnetic field generating apparatus 120 at optimum timing respectively.
That is, as shown in FIG. 2, by applying a magnetic field from the outside magnetic field generating apparatus 120 to a reed switch 126a of the capsule endoscope 110 a plurality of times and thereby causing an FET 126d, which is a main switch, and an FET 126e, which is an RF switch, to perform ON/OFF operation one by one, it is possible to distribute power to an LED drive circuit 121 that drives an LED 127, a CCD drive circuit 123 that drives a CCD 122 and an RF transmission unit 124 at optimum timing respectively. In FIG. 2, flip flops 126b and 126c constitute a latch circuit for a toggle operation.
In the capsule endoscope 110, the reed switch 126a turns ON/OFF by a magnetic field generated by the coils 144 and 145 and the FET 126d thereby controls a power supply from a battery 129 through the toggle operation.
Here, when the capsule endoscope is administered to a plurality of examinees, a plurality of capsule endoscopes of the same type or different types are prepared for the respective examinees. Activation/stopping of the respective capsule endoscopes needs to be controlled as appropriate.